Defecation has remained overlooked within anthropology and sociology, despite recent focus on the body. The thesis suggests that this is related to its construction as something hidden in the last few hundred years of modern Western society. It is physically and mentally dismissed as personal and biological rather than social or cultural. The few references that exist enable one to argue that it always has significance as a repetitive daily activity needing careful social management and which is crucial to the definition of personhood. Its praxis reveals much about social values concerning differentiation by age, sex, gender and generation. Freud, Elias, Bakhtin and Douglas have influenced its image but do not adequately explain it. Phenomenological theories of embodiment and ideas of cultural performance are shown to be more useful in demonstrating that defecation is a lived cultural experience. The focus is on contemporary Britain, studied through participant observation and day-to-day participation, using material from conversations, anecdotes, observations, experiences, media reports, novels, and films encountered during the period of research. The main themes that emerge are privacy, hiddenness, embarrassment and concern but also that it is welcomed as physical release, and as offering valued periods of time-out and solitude. It is also a symbol of both all that is low and all that is deep. These contradictions are analysed through the two axes of control/loss of control and release/containment. It is argued against recent medical anthropological and sociological studies of incontinence that it cannot be assumed that the opposite of incontinence is continence and containment. The issue of control is paramount, rather than the issue of containment in itself.